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## #326 2014-01-14 04:28:39

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

Hi;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #327 2014-01-14 04:43:07

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

Hi,

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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## #328 2014-01-14 04:48:13

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

Hi;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #329 2014-01-14 05:00:46

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #330 2014-01-14 05:05:38

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #331 2014-01-14 05:16:02

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #332 2014-01-14 05:18:05

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #333 2014-01-14 05:24:38

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #334 2014-01-14 05:29:38

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #335 2014-01-14 05:39:11

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #336 2014-01-14 05:41:36

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

Hi;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #337 2014-01-14 05:46:52

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #338 2014-01-14 05:50:37

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #339 2014-01-14 05:53:21

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #340 2014-01-14 05:57:34

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #341 2014-01-14 06:03:26

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #342 2014-01-14 06:10:40

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #343 2014-01-14 06:15:07

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

Last edited by gAr (2014-01-14 06:20:24)

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #344 2014-01-14 06:21:18

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #345 2014-01-16 18:07:32

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

New problem:

i. What is the expected value of the variable c in the following snippet of code?

``````c=0
a=0
while (a!=0xffffffff)   # loop until all 32 bits in 'a' are 1
i=random(0,32)      # get a random number between 0 and 31
a=a|(1<<i)          # set the i'th bit from right in a 32 bit integer 'a'
c=c+1               # increment c``````

ii. If 'a' is a n bit integer, what is the expected value of c till all n bits are set?

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #346 2014-01-16 20:57:44

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

Hi gAr;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #347 2014-01-16 21:01:01

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

Hi bobbym,

Okay.

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #348 2014-01-16 21:10:21

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Probability problem.

Hi;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

## #349 2014-01-16 21:39:43

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

Hi bobbym,

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

## #350 2014-01-16 23:30:18

gAr
Member
Registered: 2011-01-09
Posts: 3,481

### Re: Probability problem.

A modified version of the previous problem:

iii. What is the expected value of the variable c in the following snippet of code?

``````c=0
a=0
while (a!=0xffffffff)   # loop until all 32 bits in 'a' are 1
i=random(0,32)      # get a random number between 0 and 31
a=a^(1<<i)          # toggle the i'th bit from right in a 32 bit integer 'a'
c=c+1               # increment c``````

iv. If 'a' is a n bit integer, what is the expected value of c till all n bits are set?

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline